how to fix P0174 code on Toyota RAV4 XA50 (2019-2024)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal.
• Ensure the vehicle is parked on a flat surface and the engine is cool.

2. Inspect and Clean MAF Sensor

• Tools Required: MAF sensor cleaner, Torx screwdriver
• Remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with MAF cleaner to remove dirt and debris.
• Allow it to dry completely before reinstalling.

3. Check for Vacuum Leaks

• Tools Required: Smoke machine or carburetor cleaner
• Inspect all vacuum hoses for cracks or disconnections.
• Use a smoke machine to identify leaks or spray carburetor cleaner around suspected areas while the engine is running to check for changes in RPM.
• Repair or replace any damaged vacuum hoses.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge
• Locate the fuel rail pressure test port.
• Connect the fuel pressure gauge and turn the ignition to the "ON" position without starting the engine.
• Check the pressure reading against Toyota specifications (typically around 43-50 psi).
• If pressure is low, inspect the fuel pump and filter for issues.

5. Inspect and Clean Fuel Injectors

• Tools Required: Injector cleaner kit, socket set
• Remove the fuel rail to access the injectors.
• Clean the injectors using an injector cleaning kit or replace them if they are clogged or malfunctioning.
• Reinstall the fuel rail ensuring proper torque specifications are followed.

6. Replace Engine Coolant Temperature Sensor (if faulty)

• Tools Required: Ratchet set, replacement sensor
• Locate the engine coolant temperature sensor.
• Disconnect the wiring harness and remove the sensor using a ratchet.
• Install the new sensor and reconnect the wiring harness.

7. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0174 code from the ECM.